The invention relates to modifying the surface of an article.
Surfaces of, e.g., medical devices must often be modified. For example, the surfaces of medical devices that are in direct contact with blood or blood products (e.g., blood oxygenators, blood pumps, catheters, and tubing) have been treated with biologically active agents such as heparin or derivatives thereof to make such surfaces nonthrombogenic in an effort to prevent clotting or clot formation related to surface contact with blood or blood products.